THE HUMAN GENOME:
POEMS ON THE BOOK OF LIFE
GILLIAN K FERGUSON
THE HUMAN GENOME:
POEMS ON THE BOOK OF LIFE
GILLIAN K FERGUSON
Difference
‘The human thus appears to have only about twice as many genes as worm or fly. However, human genes differ in important respects from those in worm and fly. They are spread out over much larger regions of genomic DNA, and they are used to construct more alternative transcripts. This may result in perhaps five times as many primary protein products in the human as in the worm or fly…The full set of proteins (the 'proteome') encoded by the human genome is more complex than those of invertebrates. This is due in part to the presence of vertebrate-specific protein domains and motifs (an estimated 7% of the total), but more to the fact that vertebrates appear to have arranged pre-existing components into a richer collection of domain architectures…Although about half of the human genome derives from transposable elements, there has been a marked decline in the overall activity of such elements in the hominid lineage. DNA transposons appear to have become completely inactive and long-terminal repeat (LTR) retroposons may also have done so…The pericentromeric and subtelomeric regions of chromosomes are filled with large recent segmental duplications of sequence from elsewhere in the genome. Segmental duplication is much more frequent in humans than in yeast, fly or worm.’ "International Human Genome Sequencing Consortium" International Human Genome Sequencing Consortium, Nature, 2001
‘There is little correlation between the complexity of an organism and the amount of DNA it has. The human genome contains at least 200 times more DNA than the yeast genome's 12 million bases (the letters of the genetic code), but the genome of Amoeba dubia, a unicellular creature as simple as yeast, dwarfs the human genome by 200-fold.’ Henry Gee, Nature
‘If the increasing complexity of humans isn’t due to a dramatic rise in gene number, what might explain it? No single dominant property stands out. Instead, a mixed bag of features combine to greatly enhance innovation. One example is alternative splicing of RNA: once RNA has been copied from a gene sequence, the non-coding sequences from the introns are sliced out to bring the coding sequences from the exons next to one another. By missing out an exon here and there, the splicing machinery can create novel products. Around 60 per cent of human genes have two or more alternatively spliced transcripts, compared, for example, with only 22 per cent in the worm. Another factor is the lavish supply of proteins that switch genes on or off, such as the zinc finger family of proteins. This family has expanded independently in humans, yeast, fly and worm but humans still have twice as many zinc finger proteins as the fly and nearly five times as many as the worm. Meanwhile, proteins themselves can be modified, for example by enzymes snipping bits off them, or by the addition of sugars or fats to change their activity. This builds into a picture of exquisite layers of control of genes and proteins, with genes being turned on and off, up and down, with extraordinary subtlety driving our development from fertilized egg to adult, and maintaining and repairing our bodies during the rigours of daily life.’ Wellcome Trust, 2001
Rising from the same waters; same light
and word calling us into existence – life.
Almost identical with fish and mouse,
yet utterly apart, as rulers – big-brain
creatures who have inherited the Earth -
subjugated even the Sun-King of Beasts;
ruined our subjects, altered our kingdom -
as usurpers - the irresponsible, Idiot-Kings.
But what gave us the power, organic luck,
to set us thus, apart - unlikely, weak, bald;
susceptible to so many ills, misfortunes,
hungers and woes - vulnerable to germs
we cannot even see - with cooing babies
who can’t survive the wild, even an hour.
How did we come to be here, then;
incalculably dominant - chattering
in a world of whoops, cackles, howls,
barking, neighing, miaows and hoots;
Genetic Masters, World-winners,
while written in the same script –
indistinguishable in the womb
from kangaroo or lamb, mouse
or chimpanzee. In the scientist’s
computer so magically revealed,
such close identity with Earth fellows.
What marks us out as the sons of Man,
the Different Ones ; The Others,
Alien Brothers - what chemistry
is ours, holiest among the holy
script of our simplest relatives.
*
The poem is not made with an amount of words
but what’s done with them; in grammatical skill.
A poem is not better because it is bigger -
its power lying in how the words are used;
dexterity, power, communication, imagination,
driving the human verse - line on glorious line.
Music is not made with an amount of notes -
but how they are combined; conducted, tuned,
interrelated, with notational skill; intimately scored
by natural genius, in a symphonic Human Genome.
Superior twinkling of switches
Superior twinkling of switches;
more dextrous galaxy of stars -
sophisticated mechanisms,
organic cogs; sophisticated
chemistries linking cunning shifts,
splices, enzymes, sugars – cutting,
splicing, stitching, adapting;
endless creativity over time
with what we’ve got – same,
but different; some message
in the brain - overdeveloping,
sparking new cells, language;
that will one day let us lord
about the world - mistaken
in our superiority. For what also
marks our species out; stupidity,
the only animal destroying
his own environment, home.
‘Scientists at the Sanger Centre near Cambridge decoded about a third of the genome. They deciphered the first human chromosome here just over a year ago. Although they suspected we have fewer genes than originally thought, they were still surprised to learn we have only twice as many as a fly. The obvious question then is how come we're so much more complex. A fly can fly, but generally they can't talk, or think a great deal. If it's not down to the number of genes, what is it that makes us different? The man who's led the UK effort for the past decade thinks the key is in the way we "manage" our genes.’ Horizon, BBC TV
All that separates us from the worm
All that separates us from the worm
is more ingenious shuffling of genes;
some sleight of nature’s hand: Bingo!
Well, Bingo over four billion years;
hands and eyes, artists and speech,
instead of being blackbird’s dinner.
What undeserved luck, what winning
of the creature lottery; by what drive,
ingenuity firing our evolving cells -
running away with the basic recipe;
multiplying possibilities - escaped -
sugaring and splicing, manipulating
proteins, crocheting chemicals;
managing built complexities -
high exploitation of simplicity.
Until, lo, such art and knowledge
embroidering the animal genes -
mysteriously ornate; intellectual.
‘The genes are the templates for the proteins, the sophisticated molecules that build and maintain an organism. In a complex animal like a human, a vast array of different proteins is required. The trick is in generating that diversity. In plants, evolution has chosen duplication as the preferred route. "Plants copy their genes and tinker with them to do something new," said plant geneticist Professor Michael Bevan, from the John Innes Institute in Norwich, UK. But that only gets you so far. "After a while, so many copies of genes that differ only so slightly from each other could give rise to confusion," Professor Wong said. What you need, and what animals have got, is a system for generating a variety of different protein products from a limited number of genes. It's called alternative splicing. "I liken it to a Swiss Army knife," Professor Wong told BBC News Online. "You can do a lot of different things with one tool." What is clear from the two DNA sequences of rice is that very little alternative splicing is going on. "This figure of 40-50,000 genes we found in rice is probably very close to the actual number of protein products. In humans - well, who knows? Some estimates put the number of protein products at well over 100,000," Professor Wong said.’ BBC News Online
DIFFERENCES
‘Genes that drive development by signalling between cells -
Fibroblast growth factors - Humans 30, Fly 2, Worm 2
Transforming growth factor-ßs - Humans 42, Fly 9, Worm 6
Proteins of the immune system -
Genes with immunoglobulin subunits or 'domains', (such as those in antibodies) –
Humans 765
Fly 140
Worm 64
Mustard weed 0
Yeast 0
The remaining additional genes are not primarily the result of invention of new types of protein in the vertebrate lineage - only 7% of identified protein and protein domain families are truly specific to vertebrates. Rather, new proteins come from reshuffling the number and order of protein domains, analogous to making new structures with the same Lego pieces.
If the increasing complexity of humans isn’t due to a dramatic rise in gene number, what might explain it? No single dominant property stands out. Instead, a mixed bag of features combine to greatly enhance innovation –
Alternative splicing of RNA: once RNA has been copied from a gene sequence, the non-coding sequences from the introns are sliced out to bring the coding sequences from the exons next to one another. By missing out an exon here and there, the splicing machinery can create novel products.
Genes with two or more alternatively spliced transcripts:
Human 60%, worm 22%
Another factor is the lavish supply of proteins that switch genes on or off, such as the zinc finger family of proteins. This family has expanded independently in humans, yeast, fly and worm:
The Zinc Finger Family - Humans x 2 of fly; x 5 of worm.
Meanwhile, proteins themselves can be modified, for example by enzymes snipping bits off them, or by the addition of sugars or fats to change their activity. This builds into a picture of exquisite layers of control of genes and proteins, with genes being turned on and off, up and down, with extraordinary subtlety driving our development from fertilized egg to adult, and maintaining and repairing our bodies during the rigours of daily life.’ Wellcome Trust, 2001
‘The fragmentation of human genes allows many different proteins to be built from the same genes, combining the instructions in different exons in different ways. At least 35% of all human genes, it appears, may be read in several ways. In this way the human genome could encode five times as many proteins as the less flexible genomes of the fruitfly or roundworm.’ Henry Gee, Nature magazine
Imagination, art, are not luxuries
So imagination, art, are not luxuries;
but driving forces of evolving life -
necessary tools of human evolution,
that were very keys to the kingdom
of Earth, dominance over the garden,
unlike protozoans, zebrafish, eagles.
Without ingenuity, experiment, skill -
such imaginative means of expression,
the Human Genome would not be
this embroidered work, exquisitely
seamed; gold, copper, silver-threaded
velvet - ancient silks lettered in stars -
but woven as more humble woollen
shawl, lucky with tasselled fringes -
a snout evolved for shunting darkness -
novel means of survival; though beauty
is not a human prerogative, snatched
by the peacock, tiger, hummingbird -
lion, lemur, butterfly - and all manner
of creatures far more gracious, lovely,
dark and brightly beautiful; ingenious
with molecules - physical, organic art.
But the brain crucible is the place
of fire, transmutation of elements;
first ingredients given to all, still present,
but fundamental chemistries reworked -
rebooted, sparked - carapaces of neurons -
synapses, starry clusters, burring thoughts;
recycling, storing, threading more beads,
constructing palaces - cathedrals of cells;
masterwork of seamstress, tailor -
tireless artist-embroiderer of DNA.
Though foxes, lambs and Birds of Paradise;
stoats, peacocks, weasels, even laden bees -
damselflies, dragonflies, leaves, flowers,
even mayflies; in fact everything dances -
and singing birds also evolved music;
even in dreams rehearse fresh songs.
‘There are, on average, around 12 genes per million bases of human DNA, compared with 117 in fruit flies, 197 in roundworms and 221 in Arabidopsis.’ Henry Gee, Nature magazine
‘The first wave of information from the analysis of the human genome revealed SNPs to be the main source of genetic and phenotypic human variation. However, the advent of genome-scanning technologies has now uncovered an unexpectedly large extent of what we term 'structural variation' in the human genome. This comprises microscopic and, more commonly, submicroscopic variants, which include deletions, duplications and large-scale copy-number variants - collectively termed copy-number variants or copy-number polymorphisms - as well as insertions, inversions and translocations. Rapidly accumulating evidence indicates that structural variants can comprise millions of nucleotides of heterogeneity within every genome, and are likely to make an important contribution to human diversity and disease susceptibility.’ Nature, 2006
‘Any sufficiently advanced technology is indistinguishable from magic.’ Arthur C Clarke
‘Functional and evolutionary classification - We began by classifying the human proteome on the basis of functional categories and evolutionary conservation. We used the InterPro annotation protocol to identify conserved biochemical and cellular processes…The proportions of the yeast, worm, fly and mustard weed protein sets that are assigned to at least one InterPro family is, for each organism, about 50%...About 40% of the predicted human proteins in the IPI could be assigned to InterPro entries and functional categories. On the basis of these assignments, we could compare organisms according to the number of proteins in each category. Compared with the two invertebrates, humans appear to have many proteins involved in cytoskeleton, defence and immunity, and transcription and translation. These expansions are clearly related to aspects of vertebrate physiology. Humans also have many more proteins that are classified as falling into more than one functional category (426 in human versus 80 in worm and 57 in fly). Interestingly, 32% of these are transmembrane receptors.’ International Human Genome Sequencing Consortium
Human life, as distinguished from a leaf
Human life, as distinguished from a leaf;
aardvark, kangaroo, magnolia, earwig -
is merely a question of degree; complexity
of pattern - communication, management.
Created with the same tools, ingredients,
but shuffled with more imagination, flair,
experiment; rehearsing, taming, assimilating,
borrowing from here and there – everywhere.
Learning from plastic earth how to be -
the capacity to make blood from water;
manipulating genes until contemplation
of stars, work of those genes, is possible.
‘We quantified the number of distinct protein architectures found in yeast, worm, fly and human by using the SMART annotation resource. The human proteome set contained 1.8 times as many protein architectures as worm or fly and 5.8 times as many as yeast…A related measure of proteome complexity can be obtained by considering an individual domain and counting the number of different domain types with which it co-occurs. For example, the trypsin-like serine protease domain co-occurs with 18 domain types in human (including proteins involved in the mammalian complement system, blood coagulation, and fibrinolytic and related systems). By contrast, the trypsin-like serine protease domain occurs with only eight other domains in fly, five in worm and one in yeast....Among chromatin-associated proteins and transcription factors, a significant proportion of domain architectures is shared between the vertebrate and fly, but not with worm. The trend was even more prominent in architectures of proteins involved in another key cellular process, programmed cell death. These examples might seem to bear upon the unresolved issue of the evolutionary branching order of worms, flies and humans, suggesting that worms branched off first. However, there were other cases in which worms and humans shared architectures not present in fly. A global analysis of shared architectures could not conclusively distinguish between the two models, given the possibility of lineage-specific loss of architectures.’ International Human Genome Sequencing Consortium
Contemplation of whether we were longer worm or fly
Contemplation of whether we were longer worm or fly
is a phantasmagorical conversation of science; imagine
the water-cooler chat, sofa-analysis of this unreal parade
of new relations - what humility might be born, laughter
at who is more still the worm and who the yuck bluebottle
boyfriend - what we’d call low-life - but whose repulsive
blue body is the navy night sky hardened into exoskeleton;
he, too, has bright stars still in his tiny monster eyes - light
is captured in his windowed wings. The worm understands
with his whole body – earth; among roots, birth of flowers,
he wriggles his days, muscling along in darkness - so mild,
squiggly, pink - just digging your fingers into soil, you can
get the idea; or what should we say, now, is memory. What
brought us to light, planted our web-feet on earth, underneath
sky - some bright stirring of connected genes - new creativity
with the recipe; an act of learned artistry drawing us different.
‘Conclusion. Five lines of evidence point to an increase in the complexity of the proteome from the single-celled yeast to the multicellular invertebrates and to vertebrates such as the human. Specifically, the human contains greater numbers of genes, domain and protein families, paralogues, multidomain proteins with multiple functions, and domain architectures. According to these measures, the relatively greater complexity of the human proteome is a consequence not simply of its larger size, but also of large-scale protein innovation.’ International Human Genome Sequencing Consortium
Innovation, ingenuity, imagination;
driving forces in the art of biology,
at the cellular level - of Evolution;
as well as the intellectual, creative
force of the everyday spectacular life
of evolving, expressed homo sapiens.
‘An important question is the extent to which the greater phenotypic complexity of vertebrates can be explained simply by two-or threefold increases in proteome complexity. The real explanation may lie in combinatorial amplification of these modest differences, by mechanisms that include alternative splicing, post-translational modification and cellular regulatory networks. The potential numbers of different proteins and protein–protein interactions are vast, and their actual numbers cannot readily be discerned from the genome sequence. Elucidating such system-level properties presents one of the great challenges for modern biology.’ International Human Genome Sequencing Consortium
Where is the working of the heart written
Where is the working of the heart written,
deciphered by lettered code - Evolution’s
emotional rose - symbolic blood factory -
her seas, salts turned red, inventing passion.
Pumping organic clock - drawing her shape
on the planet - driving her slavish creature,
as red dictator, tyrant with highest motivation.
Blind in dark chest - wired to pilot, messenger
eyes; deciding everything, overriding fabulous
brain telling the best thing to do - her script
dominates, rules; even to the point of killing
the Genome’s whole work - her body, being.
Even, in extremis, under love’s black shadow,
sickle-moon time of no stars, the heart herself;
as untameable red human word, wild with love.
“The challenge for scientists is to explain how a sophisticated human can be built from around 30,000 genes, fewer than for a grain of rice, and only a few hundred more than a mouse.” Martin Bobrow, Professor of Medical Genetics, Cambridge University, UK
“We know that as we move up the ladder of complexity from the single cell creatures, through small animals like worms and flies, and up to us, what we are adding on is control genes. We are not adding so many new genes performing new functions - what we are doing is to increase the variety and subtlety of genes that control other genes.” SirJohn Sulston, Leader, Human Genome Project, UK
We are symphonic
We are symphonic - a light circuit
sparking a string of chemical fairy
lights; plotting Van Goch’s starry
night sky, or a pinball machine –
Humpty Dumpty or Keat’s Ode to Autumn;
the works of Shaespeare, or Highway Code.
Illuminating jingles or connecting
Mozart’s broadband, to wherever
music comes from before it composes
in brains, translated by a blessed hand.
Such tools given, shared, but
adapted by us magnificently –
in a way we might call magic;
religious or supernatural, and
have done, until freshly described
by science now, by other names –
in a harder language, diamond for
snowflake; meaning just the same.
‘In all there are 1000 olfactory genes scattered throughout the genome, evidence of the importance of smell to most mammals. In humans, about 60 per cent are non-functional pseudogenes, illustrating our reduced dependency on smell compared with other mammals.’ Richard Gallagher and Carina Dennis, Wellcome Trust, 2001
‘New architectures from old domains. Whereas there appears to be only modest invention at the level of new vertebrate protein domains, there appears to be substantial innovation in the creation of new vertebrate proteins. This innovation is evident at the level of domain architecture, defined as the linear arrangement of domains within a polypeptide. New architectures can be created by shuffling, adding or deleting domains, resulting in new proteins from old parts.’ International Human Genome Sequencing Consortium
‘This expansion is particularly evident in the genes that drive development by signalling between cells: humans have 30 fibroblast growth factors (fly and worm have two each) and 42 transforming growth factor-ßs (fly and worm have nine and six, respectively). Such differences are also apparent in the proteins of the immune system: humans have 765 genes with immunoglobulin subunits or 'domains' (such as those in antibodies), while the fly has 140, the worm 64, and the mustard weed and yeast have none at all.’ Where are all the genes?, Wellcome Trust, 2001
Grand High Champion of Genes
Man the Master Builder, The Star;
Grand High Champion of Genes -
Most Favoured by Spirits of Creativity;
Ingenuity, Innovation and Imagination.
Such favouritism, such pleasure potential -
as lucky receptacle of similar co-ordinates;
but Chemistry’s Pet, Grand Experiment,
Art; constructing an imagination’s subtle
means from water, stardust, light -
earth palette, pen, elemental paper;
infinity of molecular possibility -
plasticity of combination, signals.
Wellspring deep into original darkness,
where what is, becomes dim, obscure -
even Laws are beautiful; mysterious
still. And love, as first energy of life,
Universe, seems as likely a way
to explain such forces as others.
‘With all animals with lots of cells, including flies and worms, you need managers to organise how one cell is different from another. They are the executive structure. In flies and worms, you have a certain executive structure. In going from them to humans, what you build more than anything else is the executive structures. You get many more layers of management - people reporting to each other - in genetic terms. We know that because we can look in there and see that the extra genes in humans compared to flies and worms belong more in the management class than in any other class. What we don't know is how those managers fit together. That's what we'll find out now.’ Sir John Sulston, Horizon, BBC TV
‘The genome has come to do much more than it could possibly have been designed to do.’ Henry Gee, Genome Gateway, Nature
What Dreamed the Hand and Eye
What dreamed the hand and eye
of man, his shining mechanisms;
star-bone, earth-glass,
so delicately written -
booming red heart,
as dark blood-rose
in his blacker breast, shouting
louder even than the brain -
freakish sparkling cauliflower -
risen electrical from first water;
jumping to Chaos Theory from stone
arrow, banana skin, Promethean fire,
in history’s outermost epidermis -
what leg-up did Homo Sapiens get?
Is this influence of a creative God;
what made-in-his-image means? –
God is the mouse and lichen too;
tiger, lily - Polar Bear, and leaf -
but touching our invisible Genome root,
scripted bulb in the mysterious darkness
of space and time, somewhere among stars,
seed and means, writes illuminating lines -
of image not skin, spotted fur, blonde hair -
photosynthetic green, African chestnut eye;
but texture and power of spirit - soul-colour;
unconscious realisation, articulation of love.
There our difference and similarity -
our profound aspiration; knowledge.
‘Finding out we have only twice as many genes as a fruit fly might be a good lesson in humility, but does it tell us anything useful? Well, for scientists it confirms long-held suspicions that what really makes us individuals is decided not in our genes in themselves but in the way our bodies interpret these genes and that's the next 50 years of biology. ‘ Susan Watts, Newsnight, BBC TV, 2001
‘...it is not how many genes you have, but how you use them Introns in the fruitfly and roundworm have a 'preferred' length, tens or at most hundreds of bases long. Human introns are much more variable. Most are around 87 bases long, but a substantial population are very long, the average length up to more than 3,300 bases. Exons, in contrast, can be very small indeed, and therefore easy to miss - more than 40 are known in the human genome that are each just 19 bases long. The human genome could encode five times as many proteins as the less flexible genome of the fruitfly.’ Henry Gee, Genome Gateway, Nature magazine
By the artist’s concentrated grace -
The same ground pigment makes a face -
A river, steeple, church tower,
Apple, sunset, or white flower.
Infinite possibilities within the frame -
So few ingredients but never the same;
As writer spinning page to book,
Dancer’s steps, the way we look;
So skilful proteins dance and part -
Already in DNA, we reach for art;
Cells in the holy dark create -
Myriad dazzling pairs gyrate.
‘A man coming out of a bath carries with him a film of water of about one-fiftieth of an inch in thickness. This weighs roughly a pound. A wet mouse has to carry about its own weight of water. A wet fly has to lift many times its own weight and, as everyone knows, a fly once wetted by water or any other liquid is in a very serious position indeed.’ JBS Haldane, Possible Worlds and Other Essays, Chatto & Windus, 1927
‘The most obvious differences between different animals are differences of sizes, but for some reason the zoologists have paid singularly little attention to them… For every type of animal there is a most convenient size…To the mouse and any smaller animal [gravity] presents practically no dangers. You can drop a mouse down a thousand-yard mine shaft, and, on arriving at the bottom, it gets a slight shock and walks away. A rat is killed, a man is broken, a horse splashes…divide an animal’s length, breadth, and height each by ten; its weight is reduced to a thousandth, but its surface only to a hundredth…an insect, therefore, is not afraid of gravity; it can fall without danger, and can cling to the ceiling with remarkably little trouble. It can go for elegant and fantastic forms of support like that of the daddy-long-legs…’ JBS Haldane, Possible Worlds and Other Essays, Chatto & Windus, 1927
Insect-astronauts
Insect-astronauts; exploring, feeding
in Earth’s orbit - broken free of air’s
invisible chains; oxygen molecules
binding us down to ground, heavy
with poundage – clanking casket
of marble bones in silencer skin,
improbably balanced on a few shod inches -
so tender our grasp of balance; observe how
arms instinctively rise, as if wings still spread
to help – we can remember something of how
it was, when we jump and water holds us up -
but unhelmeted Bluebottle rose from maggots
with dark hallelujahs to inherit open sky;
ceilings, nutritional elements of carrion -
understanding gravity as a tool allowing launch,
descent, through space turned treacly enough –
with the right genome, interpretation of skeleton -
the fruit fly, angels maybe - in some dark culture
still unknown; unspoken insect micro-mythology -
where butterflies and moths are day and night gods;
as kingdoms of bacteria battle, harvest humans -
bring down murdered creatures into soil-mouth;
bloom fungi at the place enriched – fertile
gravestones, living memorials of repulsive
beauty - from the same dark art as ink-black
exoskeleton gleaming in reluctant sunshine -
which prefers flowers, green; easier beauties
of perfume, colour and light, but will accept -
offering a translucent brown glow
to the drifting ethereal crane-fly -
dangling delicate threadlegs
on a droopy passive flight -
just held in existence by so few cells;
crushed, she is a rickle of one word’s-
worth of lines - a scribble - her biscuit-
dry hair-bones in fundamental disarray,
too brittle for blood. Yet will land,
symmetrically splayed on muslin
curtains with perfect deportment;
haunt the room with mechanical
clockwork whirring, as if Leonardo da Vinci
had drawn her - and she, risen from the page.
How awful when they batter themselves,
our insect astronauts circling in Earth’s
clear atmosphere, headfirst into hot lights -
car lamps, trickster window glass; so noble
in bewildered perseverance - as if even
the tiny blue-black spark of a bluebottle,
for all his differences of beauty, still
is governed by light - also returning.
‘Scientists have discovered a ‘genetic arms race’ in mice that has been running for millions of years…Research led by Professor Chris Ponting from the Medical Research Council’s Functional Genetics Unit analysed mouse proteins and genes uncovered by the genome project…The team discovered that pieces of the mouse genome have evolved faster than others, giving a greater insight into how genes in humans and mice work. Although four-fifths of genes are now known to be held in common between human and mice, the Oxford team found that gene differences hold the key to understanding recent evolution…This in turn will help in understanding health and disease. When scientists looked at the genes which have changed the most over the past 75 million years they were found to be involved in life-or-death competition. This may be either between members of the same species for food, environment or choice of mates, or between a species and its parasites. This highlights the ‘genetic arms race’ running both within a species, and between different species. The mouse immune system is engaged in an arms race with bacteria and viruses that prey on the animal, with each under strong pressure to respond to changes in the other’s genome. This has been going on for millions of years with mouse genes changing to rid themselves of the viruses and parasites, and the latter in turn evolving to maintain their survival. Reproductive struggles among mice have also generated large-scale genetic change. The study showed that, compared with those in humans, pregnancy hormones in mice have changed dramatically. This is likely to reflect the different reproductive strategies they employ. Mice go for large litters many times a year, whereas humans invest more time and greater energy on fewer young. Professor Ponting from the MRC Functional Genetics Unit, said: “It is as important to understand what makes us different, as what makes us similar, to other animals. It’s fascinating to see how each species has adapted to its own ecological environment. Now, though, we can use the new genome sequences to reveal how conflict has remodelled the animals down to their very genes.’ ref
Genetic arms race under the surface
Genetic arms race under the surface
of a creature – stability is principle,
not static rule; a necessary illusion
for comprehension, activity or peace.
But the dancing never stops, falters -
not one hair of any second ever stops
moving, vibrating to some old music
that still shifts molecules - and now -
conducted by life, brilliant chemistry
at work for four billion years -
shaping her creatures - illusory
boundaries perceived by vision
as one beautiful tiger - complete
starry mouse twinkling out from
twilight skirting - heart fluttering
at a speed hummingbirds understand;
similarly accelerated by the genome
as being advantageous - in defeating
the forces of mammal disadvantage,
whose genomes partake of dark arts;
destructive, damaging - like cancer
tripping the right genetic switches
at the wrong time - parasites using
warm bodies as home, as nurseries;
cunning viruses outwitting defences
in the cell - even the human brain’s
capability for external examination
of such entities - permanently at war
then, for this peace means bad death,
avoided by life as an unintended end.
‘Five thousand mice weigh as much as a man. Their combined surface and food or oxygen consumption are about seventeen times a man’s. In fact a mouse eats about a quarter of its own weight in food every day.’ JBS Haldane, Possible Worlds and Other Essays, Chatto & Windus, 1927
What they can do for us
Maybe the impulse to overeat comes not from shared genes
with poor metaphorically-blamed pigs, but tiny wee slivers
of skinny mice! Eating a quarter of your body weight every day –
PMT rations and some, without gaining as much as a single ounce;
ah, sounds bliss. Indeed, they seem to weigh as much in the palm
as dandelion seed, Chinese lantern, dry leaf - and if we could add
in the hollow bones making birds light as fairies - a smatter of stork
to thin and elongate the leg, all these differences could be harnessed
by the power of genetic similarity. And no doubt one day someone
irresponsible, clever, just greedy enough, will concoct such potions;
and some woman insecure to the point of stupidity, will knock
back a draught of ‘Genetic Giraffe-Slim’ to be taller, thinner -
with fatter eyelashes; a man grow tigerskin down his back,
stag horns for a Saturday night - a dark woman, kingfisher
flash in her raven hair. No doubt when we have finished
with what they can do for us being hunted, dead, used -
we will think up novel ways to exploit their living patterns,
always wondering what they can do for us, not us for them;
breeding alligators handbag-shaped - sheep dyed in the wool,
half instant knitted jumper; oven-ready silver fish in scaly foil;
goats and rabbits in crippling amounts of angora and cashmere;
genetic transplantation of the stolen means of song from birds -
stealing dragonflies’ iridescence for our eyes, our contact lenses;
wearing the plumage of a peacock as surveillance robe; and just
bred for the customers of haute couture, tailored to size six -
the last leopards and tigers worn by some fucking rich bitch.
‘A mouse’s eye is not a small-scale model of a human eye. Its rods and cones are not much smaller than ours, and therefore there are far fewer of them. A mouse could not distinguish one human face from another six feet away. In order that they should be of any use at all the eyes of small animals have to be much larger in proportion to their bodies than our own.’ JBS Haldane, Possible Worlds and Other Essays, Chatto & Windus, 1927
They did not grow these large eyes to look cute to us -
feature in cartoons as some acceptable, must-save face
of Nature - but as bright, organic, technical instrument;
drawn from life’s same sheaf of casual miracles - being
triumphs of chemical art so fabulous, they belong to the
same genus. Constructed in darkness from external light;
not quite possible, but visible, there. Shining molecular
embroidery of such momentous scale, stars have grown
old as they watched – just the eye more astounding than
the face of Jesus seen in a loaf of bread - Elvis appearing
in a concrete floor; or water becoming a fish, bird or man.
Let me remember I am leaf, bird, and animal
Let me remember I am leaf, bird, and animal;
different only in sophistication of chemistry -
what the physical imagination of my species
has done with bright switches and shuffling -
orchestration of the genetic lettering,
in this living laboratory we call body.
Let us remember our common root;
worm and soil, sea and first light -
reaching for life, coagulating cells;
all aspiring to live, thrive, replicate.
Let us reflect our belonging to the garden,
in some new love and husbandry of Earth.
‘The draft sequence has revealed intriguing differences between the mobile elements of different species…McDonald’s group has found that the mobile elements in small genomes, such as that of the worm Caenorhabditis elegans, are much younger than those in large genomes, as those of plants and humans. This suggests, he says, that mobile elements are actively purged from smaller genomes. How, though, is a mystery. Not surprisingly then, human DNA contains a higher density of mobile elements than the genomes of other animals sequenced so far. Also, different types of mobile element are more or less equally represented in the genomes of the worm, fly and the plant Arabidopsis. In the human genome a few are in the large majority. In fact, most of the human genome's mobile elements stopped being mobile millions of years ago, before human beings evolved. Much of this may be due to mammals' advanced immune systems, which seem to have put a stop to a class of elements that relies on jumping between species to persist.. The mouse genome, unlike the human, still fizzes with active retrovirus-like elements. The most likely reason for the difference, says Arian Smit, a member of the genome analysis group who works at the Institute of Systems Biology, Seattle, are the bottlenecks experienced in human populations. "Mobile elements - like normal genes - are more likely to become dysfunctional in an inbred population," he says. McDonald, however, is cautious of drawing too many conclusions from comparisons so far, suspecting that there are many more as yet undiscovered species of mobile element within the human genome. "What we're seeing is the tip of the iceberg," he says.’ John Whitfield, Nature 2001
So much happens in the invisibility of life
So much happens in the invisibility of life -
among organic darkness we cannot witness
with our eyes made from light - adaptation
of earth into natural glass. In musical space
where stars and planets are volatile, explosive
while looking like a holy map of lights, calm
enough to wish upon - plot futures, represent
eternity and changelessness; offer perspective,
a twinkling reassurance of our passing nature.
Among the Genome’s sparkling chemistries -
mobile elements, retroviruses - species genes
marking one creature from another; eventually
seen by us as different, recognisable - honing
her art in the creative dark, until you and I can
see each other - the cultured potential for love.
‘A comparison of the chimp and human genomes casts new light on why the two species are so different despite having very similar genetic code. Scientists have long speculated over what makes humans so different from their closest relatives, the apes. One of the leading scientists on the project says the answer lies in the process that orchestrates the genes as the chimpanzee is developing. The human and chimpanzee genomes differ by just 1.2% between the coding genes. Professor Svante Paabo, from the Max Planck Institute, Leipzig, Germany, is investigating which genes are present and the manner in which they are expressed. In particular, he believes the key lies in the degree to which they are expressed in each species. "It's about the extent to which genes are turned on, where and when in the brain. "What we have now done is systematically looked at gene activity in the brain of chimpanzees, humans, orang-utans and macaques and when we compare them the surprising finding is that we actually find quite a lot of differences. And in any particular part of the brain about 10% of our gene activity differs from those of chimpanzees," said Dr Paabo. The key to the distinction between the two species could lie in the functional importance of different levels of gene expression. By mathematically modelling the changes seen in gene expression between the two species, Paabo hopes to identify those genes which could have been acted on by natural selection more strongly than others. There are also small but important differences between the individual genes. So far Dr Paabo has found two tiny but important differences in the gene FoxP2, thought to be responsible for speech and language skills. Chimps are much better at sniffing things out than we are, so unsurprisingly there are differences in genes associated with smell. "The gene involved in our sense of smell encodes for receptors in our noses, and we have found that we are losing a large fraction them and are becoming progressively worse at smelling," Professor Paabo said. "So as our language ability has improved, our sense of smell has deteriorated. The other gene is that which has been positively selected for speech and language ability within the last 200,000 years or so." There are likely to be many more subtle differences as groups across the world begin direct comparisons. In particular the Human Genetics group at the Sanger Institute in Cambridge is intrigued by why chimps are immune to many human diseases, such as malaria and Aids. According to Dr Tim Hubbard: "By looking closely at the variation of disease genes between Chimps and humans we'll gain a greater understanding of disease processes which in turn may lead to the development of better medicines." BBC, 2006
Even in difference, enlightening seeds of similarity;
what speech and language have done to dominance
over the garden; to communication, society. Words
as central elements, as in all things; speaking names
for objects, inventing metaphor, story for explanation
of everything; even those things poorly understood -
beautiful approximations, never meant as literal grace.
The Human Brain is the Flower of Creation
The human brain is the inspired flower of Creation,
Evolution’s art; cradling speech, thought, language.
Ugly internal crown sparkling with electrical stars,
neural galaxies in our internal universal darkness -
from chemistry comes love, imagination, curiosity;
pushing the boundaries from here, to conundrum -
bone-globe, skull-world, flesh-flower - opening,
closing, two doors spectacular as Sun and Moon.
‘A third of the world's primate species now face extinction. Scientists warn that our closest relatives, the great apes, could be extinct in 20 years' time. The commercial bushmeat trade, human population growth, the tropical hardwood industry, war, deforestation and habitat loss all threaten their survival.’ BBC, 2006
Come into my forest now
Come into my forest now with tender feet;
tred on the muffling litter of fallen leaves -
share fruit with me while I show you
how to live without disturbing here -
the collective spirit of green and creature;
season, product, and recycling principles.
Yes of course there is death, natural
to the scheme of things, as essential,
but not one life goes unrecorded;
and so each passing is honoured
by life instead of surrendered to death
as the end; eternal life is already here -
in the baton of life formed from earth,
water - passed through every species -
that led us here to verdant air, plump
fruits, running water. We are content,
with everything we need; such ignorance
we have is of no matter here – our skills
are of home, where we belong; surviving
all these aeons among the brotherly trees.
Come now, let us travel to the dim interior,
where none of your steps have trod; silence
is almost possible here – lie down,
be at peace with great holey leaves
overhead, educated just by being green;
simply enjoy filtered sun splashing skin
with pleasureable buttery slashes…
But you cannot stop at such rest –
already the leaf grows fingers in the sky;
banana in your hand looks like the Moon.
‘Natural selection is the process by which genes change their sequences. In the process of changing, though, those genes laid down a record of our four-billion year biography as a biological lineage. They are, if we only know how to read them, a more valuable source of information on our past than the manuscripts of the Venerable Bede. In other words, a record of our past is etched into our genes…science still has only the vaguest clues about how growth and form are generated by genes - but that genes are responsible is not in doubt.‘ Matt Ridley, Genome: The Autobiography of a Species in 23 Chapters, Fourth Estate, 2000
Tear Genome
Nobody knows why tears evolved;
in all Creation, only humans cry -
water spawned from original ocean
molecules, rhythmically nurtured on
a planet turned green from stardust -
holding sea-light, still bright and salty.
A mysterious symbiosis of water and emotion -
evolved physical and psychological mechanism;
scripted and organic as all life. Invisible love -
in liquid suspension, as physical manifestation
of human empathy, self care; the arcane,
sensitive chemistries of pain, hurt – joy,
dissolved to a shining clarity - the mouth
of a tiny personal spring in each glass eye,
whose currents are sourced by the master
heart - which also transformed the magic
plastic molecules of ocean enclosed, to red;
messenger blood of oxygen, iron - passion.
Written unbidden, only by reflexive eyes,
permanently ducted to this alchemic well;
transparent art of genius chemistry,
uncontrollable symptom – evidence
of the unique nature of the human being;
his possible beauty, gorgeous responses.
For no reason anybody yet can fathom,
the mark of us; another unique species
trophy awarded by generous Evolution -
never to be shed without shining, falling
.
in a dark, dry and fiery Universe.
Original light still visible there -
held in human solution; captured
from the first explosive stars, and
that wet light across the conjured waters -
as witnessed yet in every fellow raindrop,
cup of dew crying in a flower’s head -
illuminating a whole transfigured face,
as jewels are cupped by gold;
dressing it in human holiness.
In these small mysteries -
the poem of an eye crying;
much about life is written -